Equal Distribution Bus Bar for Battery Pack Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Middle- or large-sized battery packs for electric vehicles face reduced lifespan due to internal resistance differences between battery modules, leading to uneven current distribution and degradation, which is difficult to manufacture and maintain with existing bus bar technologies.
Innovation Solution
A bus bar with evenly spaced distribution circuits of the same length connecting battery modules to an external circuit, using a conductive connecting member with through-holes for uniform internal resistance and preventing short circuits with insulative coatings.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If conventional bus bars with different length connection circuits are used, then the battery pack can be assembled with flexible module positioning, but internal resistance differences occur leading to uneven current distribution and reduced battery lifespan
Solution Approach 1:
The patent applies equipotentiality by designing distribution circuits with equal lengths from the external circuit connection point to each battery module connection point. This ensures that all battery modules experience the same internal resistance regardless of their physical position, creating electrically equivalent conditions for all modules. The equal-length circuit design eliminates potential differences caused by varying connection lengths, thereby preventing uneven current distribution and extending battery pack lifespan while maintaining flexible module positioning.
Solution Approach 2:
The patent changes the critical parameter of connection circuit length from variable to constant. By setting all distribution circuits to the same length, the internal resistance parameter becomes uniform across all battery modules. This parameter standardization ensures consistent electrical characteristics regardless of module positioning, resolving the contradiction between positioning flexibility and current distribution uniformity.
2Reliability
If connection circuits are designed with different lengths or thicknesses to equalize internal resistances, then current distribution becomes uniform, but the connection circuits become complicated in shape and difficult to manufacture
Solution Approach 1:
The patent applies local quality by making the connection circuits uniform in length and cross-sectional area throughout their entire length. Instead of varying dimensions at different locations to achieve equal resistance, the design uses consistent dimensions locally at every point, which simplifies manufacturing while achieving the global goal of uniform current distribution. This approach eliminates the need for complex calculations and custom-shaped connection circuits.
Solution Approach 2:
The patent inverts the conventional approach by not trying to compensate for different distances through varying circuit dimensions. Instead of making circuits of different lengths/thicknesses to equalize resistance, it makes all circuits the same length and relies on the conductive connecting member to provide equal resistance paths to all battery modules, thereby simplifying the connection circuit design while achieving uniform current distribution.
3Manufacturing precision
If different connection circuits are manufactured for each battery module position, then internal resistances can be equalized, but manufacturing precision requirements increase and production complexity increases
Solution Approach 1:
The patent applies universality by designing a single standardized connection circuit that can be used for all battery module positions. The uniform-length distribution circuits and standardized conductive connecting member create a universal connection solution that works regardless of module positioning. This eliminates the need to manufacture different connection circuits for different positions, reducing production complexity while maintaining internal resistance equalization through the symmetric design of the conductive connecting member.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution ensures uniform current distribution across battery modules, preventing degradation and extending the battery pack's lifespan by maintaining consistent internal resistance, even under high current conditions.
Implementation Method 1
a bus bar for connecting two or more devices to an external circuit, the bus bar including a connection circuit connected to a connection point of the external circuit, and a plurality of distribution circuits having the same length from an end of the connection circuit to connection points of the respective devices
Implementation Method 2
preventing short circuits with insulative coatings
Data Source
Figure 1~2
Figure 3
Figure 4
AI summary
Disclosed herein are a bus bar for connecting two or more devices to an external circuit, wherein the bus bar is capable of equalizing internal resistances between a connection point of the external circuit and connection points of the respective devices, and a middle- or large-sized battery pack including the same. The bus bar according to the present invention reduces the difference of internal resistances due to a circuit to allow a battery module having optimized performance and a middle- or large-sized battery pack including the same to be manufactured.